The present invention relates to clamping devices and more particularly to clamping devices that are used to mount mating dies or mold sections onto the faces of platens such as those of die casting machines.
In conventional machines, whether used for casting, forging, stamping, molding or the like, die sections are mounted on platens within the machine. Commonly a number of clamps are used to mount each die section upon the appropriate platen face. Each die section generally includes recesses in the sides thereof providing an outwardly extending flange that abuts the face of the platen and provides a means for clamping the die section against the platen. The clamps are generally mounted on the platen in T-shaped channels that extend along the platen face.
One well known clamp includes an L-shaped clamp member which has one leg extending into the side recess of the die over the flange which abuts the platen, thereby forming a clamping arm, and another leg extending downwardly and contacting the platen to provide a fulcrum about which the clamping arm pivots. The threaded end of a T-bolt extends through the clamping arm and a nut is threaded over the bolt to tighten the clamping arm against the die flange. When a number of such clamps are clamped down against the die, the die is firmly secured to the platen face.
More recently, another type of clamp was introduced having ramped undersurfaces along a forward portion that contacts a wedge positioned on top of the die flange. This type of clamp is tightened down on the die by forcing the clamping arm over the wedge located on the die flange and forcing the ramped undersurface firmly against the wedge.
Although the above clamping mechanisms operate adequately to mount a die upon a platen, with such clamps it is normally difficult and time consuming to change dies on the platens. An operator is required to reach in between the spaced platens with tools in order to position and release or tighten the clamps. This reaching in between the platen faces presents a potentially severe safety hazard. Additionally, particularly in large machines, the platens are relatively large and the clamps may therefore be recessed quite a distance from the edge of the platen. It is extremely ackward to reach in between the platens such a distance and still retain enough stability to be able to tighten or loosen the clamps. Further, such machinery usually includes a large amount of hydraulic lines, housing members, controls and other equipment in the vicinity of the platens. Such equipment blocks entry to the platens and makes access back into the clamps difficult.
Time consuming die changes increase the down time for the machine and greatly reduce the machine's output. Further, die changing has heretofore been a totally manual process which increases the labor costs associated with each end product.